Refurbish 45 year old 5kv Switchgear????

[dithomas]

We have a client with 45 year old Westinghouse 5kV DH switchgear. We have recommended new switchgear but the client has asked for the cost to refurbish the existing gear. At a minimum all breakers would need to replaced with vacuum retro fill breakers, all relays and controls would need replaced, and the existing Main-Main auto transfer equipment would need to be replaced.

As a Westinghouse service engineer in 1980 I recommended that the gear be replaced. The facility, which was used for manufacturing, shut down and has been converted to warehousing. I may have been the last person to service this gear.

Other than the usual comments about safety and obsolete parts, I would like to have some comments on thoughts.

 

[jschwei314]

Maybe THEY would take to Med Volt Switches.

There are companies that make electric operated switches if THEY need an automatic throw over scheme.

 

[dithomas]

The design we proposed to replace the existing DH gear includes MEB main tie main switch/MVP-W and fused load break switches for the feeders.

We will not touch the old gear but the folks at the client are board members that have no idea.

I am looking for comments that justify junking the old gear.

 

[rbulsara]

Just curious, are you a vendor or consulting engineer? If a vendor advise them to seek opinion of an independent consulting engineer.

If this is for warehousing, they should not need sophistication and automation of a manufacturing plant. So I agree with the suggestion of MV fuse/switch metal enclosed gear.

A cost estimate and comparison of the two options and explanation of the above (if it is in line with your assessment as well) should do it. If the client still insists, it is their call.



Rafiq Bulsara

http://www.srengineersct.com

 

[alehman]

By the time you replace the breakers and relaying, it's probably less expensive to buy new, especially if you can use fused switches.

Alan
----
"It’s always fun to do the impossible." - Walt Disney

 

[xxjohnh]

It could be cheaper to buy new vacuum gear with multifunction relays. Do a real cost estimate.It would be half the size if that helps. If it is a seismic zone that would help your case as well.

 

[dithomas]

Thanks to all.

The refurb is in he range of 750K$ and the proposed new gear is 250K$.

Dan

 

[Zogzog]

How are you getting 3x the cost to refirbish versus replacement? There are a ton of roll in replacements for these breakers and they can be done at a fraction of the cost of new, not to mention the cost of the downtime for replacement. Also replacement parts for the existing DH gear are readily available.

 

[dpmac]

You would have to have quite a few breakers to come close to 750K. We did a small project in Mexico with only 10 breakers (50DHP-250 IEM units)) complete with new doors, DT3000 relays and controls for a small fraction of 750K.

 

[Zogzog]

You could get 50 VCB replacements for that, must be some warehouse.

How many breakers you talking about?

 

[dithomas]

There are 20 breakers, All of the doors with new relays and controls , new Pt's and CT's plus a new Auto Main Main auto transfer scheme plus the labor to field wire all and commission at a minimum.

The gear has actually been in service for 56 years.

What would you all be willing to leave in place and warranty the project????

 

[Zogzog]

Is there somehting wrong with the CT's, PT's, and relays? Doors? Is this gear a rust bucket? Why all the expense with an auto transfer scheme for a warehouse?

 

[dithomas]

Zogzog,

The RFQ indicated recondition to be meet current standards.

This is the global headquarters and automated warehouse for a major retail chain that requires a reliable system with auto transfer. There are two 40kV Utility feeds and two primary transformers at 5MVA each.

Reconditioning this gear is not really an option at this point.

Why would you consider leaving 56 year old induction disc relays, PT's and CT's, and and obsolete transfer scheme in service?

How would you warranty your engineering and work???

 

[Zogzog]

To meet which standards? I would test all the existing equipment per NETA/ANSI standards to determine the condition of the equipment to do a full evaluation. You have not provided any testing info, only that you recommened it be replaced in the 1980's, no basis for this recommendation was given besides it is old. The old saying applies here, they don't make stuff like they used to. I have seen much older equiment than this that was properly maintained and tested. But you obviously have already made up your mind to replace with new, I am guessing you are a vendor as someone above asked, so I am not sure what you are really looking for here.

 

[mgtrp]

"It would be half the size if that helps."

Funnily enough, I was involved with a project that involved refurbishing and replacing equipment that dated back to the 19th century. It came as a shock to many involved that a lot of the new equipment would be larger than the original. Something to do with enclosing live bus-bars, providing something passing as controls for generators, meeting 21st century safety standards, etc...